BAGRAM AIR FIELD,
Afghanistan (AP) — On a swift, secretive trip to the war zone, President
Barack Obama declared Tuesday night that after years of sacrifice the
U.S. combat role in Afghanistan is winding down just as it has already
ended in Iraq. "We can see the light of a new day on the horizon," he
said on the anniversary of Osama bin Laden's death and in the midst of
his own re-election campaign.

"Our goal is to destroy al-Qaida,
and we are on a path to do exactly that," Obama said in an unusual
speech to America broadcast from an air base halfway around the world.

He
spoke after signing an agreement with Afghan President Hamid Karzai
setting post-war promises and expectations. With two armored troop
carriers as a backdrop, Obama made his remarks in the midst of his
endeavor to win re-election as U.S. president and commander in chief.

The
president landed in Bagram in darkness, and his helicopter roared to
Kabul for the meeting with Karzai, under close guard, with only the
outlines of the nearby mountains visible. Later, back at the base, he
was surrounded by U.S. troops, shaking every hand. He ended his
lightning visit with the speech delivered straight to the television
camera — and the voters he was trying to reach back home.

"This
time of war began in Afghanistan," he said. "With faith in each other,
and our eyes fixed on the future, let us finish the work at hand and
forge a just and lasting peace."

Earlier, he delivered a similarly
upbeat message to the troops. Noting their sacrifice, he said, "There's
a light on the horizon."

It was Obama's fourth trip to
Afghanistan, his third as commander in chief. He was about seven hours
on the ground in all. He also visited troops at a hospital at the Bagram
base, awarding 10 Purple Hearts.

The written agreement that he
and Karzai signed is to cover the decade after the planned final
withdrawal of U.S. combat troops in 2014. Obama said American forces
will be involved in counter-terrorism and training of the Afghan
military. "But we will not build permanent bases in this country, nor
will we be patrolling its cities and mountains."

In his speech to the nation, Obama said, "I recognize many Americans are tired of war."

He
said that last year, "we removed 10,000 U.S. troops from Afghanistan.
Another 23,000 will leave by the end of the summer. After that,
reductions will continue at a steady pace, with more of our troops
coming home. And as our coalition agreed, by the end of 2014 the Afghans
will be fully responsible for the security of their country."

Without
mentioning the political campaign back home, Obama claimed that on his
watch the fortunes of the terrorists have suffered mightily.

Over
the past three years "the tide has turned. We broke the Taliban's
momentum. We've built strong Afghan security forces. We devastated
al-Qaida's leadership, taking out over 20 of their top 30 leaders," he
said.

"And one year ago, from a base here in Afghanistan, our troops launched the operation that killed Osama bin laden."

In
a reference to the destruction of New York's World Trade Center on
Sept. 11, 2001, he added, "As we emerge from a decade of conflict abroad
and economic crisis at home, it is time to renew America ... a united
America of grit and resilience, where sunlight glistens off soaring new
towers in downtown Manhattan, and we build our future as one people, as
one nation."

He spoke for less than 15 minutes, beginning at 4
a.m. in Afghanistan, 7:30 p.m. on the East Coast of the United States.
Minutes later, Air Force One was on its way back to Washington.

According to the Pentagon, more than 1,800 American troops have been killed across more than a decade of war in Afghanistan.

Some 88,000 remain stationed there.

Obama
flew to the site of America's longest war not only as commander in
chief but also as an incumbent president in the early stages of a tough
re-election campaign. Nor were the two roles completely distinct.

His
presence was a reminder that since taking office in 2009, Obama has
ended the war in Iraq and moved to create an orderly end for the U.S.
combat role in Afghanistan.

In the political realm, he and Vice
President Joe Biden have marked the one-year anniversary of bin Laden's
death by questioning whether Republican challenger Mitt Romney would
have ordered the daring raid that penetrated the terrorist leader's
Pakistan hide-out. Republicans are accusing the president of
politicizing the event, and Romney is insisting that he would indeed
have ordered U.S. forces into action.

Obama slipped out of
Washington, flew all night to Bagram, then shuttled by helicopter under a
moonlight sky to Kabul to help two strained allies try to turn from war
to peace â€" or at a least stable end to the war. He was greeted by
U.S. ambassador Ryan Crocker.

The deal does not commit the United
States to any specific troop presence or spending. But it does allow the
U.S. to potentially keep troops in Afghanistan after the war ends for
two specific purposes: continued training of Afghan forces and targeted
operations against al-Qaida. The terror group is present in neighboring
Pakistan but has only a nominal presence inside Afghanistan.

Obama
said the agreement was meant in part to pay tribute to the U.S. troops
who have died in Afghanistan since the war began. He also underlined his
message to Afghans.

"With this agreement I am confident that the Afghan people will understand that the United States will stand by them," he said.

Karzai
said his countrymen "will never forget" the help of U.S. forces over
the past decade. He said the partnership agreement shows the United
States and Afghanistan will continue to fight terrorism together. The
United States promises to seek money from Congress every year to support
Afghanistan.

After the signing ceremony in Kabul, Obama flew back
to Bagram Air Field. There he offered words of encouragement to
assembled U.S. troops. Obama was to be on the ground for about seven
hours in Afghanistan.

"There's a light on the horizon," he said after cautioning in somber tones that the war's grim costs were not yet fully paid.

"I
know the battle's not yet over," he said. "Some of your buddies are
going to get injured. And some of your buddies may get killed. And
there's going to be heartbreak and pain and difficulty ahead." He added
that his administration is committed to ensuring that once the war is
over, veterans will be given their due.

Officials have previously
said as many as 20,000 U.S. troops may remain after the combat mission
ends, but that still must still be negotiated.

The wars here and
in Iraq combined have cost almost $1.3 trillion. And recent polls show
that up to 60 percent of Americans oppose the U.S.'s continued presence
in Afghanistan.

The president's Tuesday night address was coming
exactly one year after special forces, on his order, began the raid that
led to the killing of bin Laden in Pakistan.

Since then, ties
between the United States and Afghanistan have been tested anew by the
burning of Muslim holy books at a U.S. base and the massacre of 17
civilians, including children, allegedly by an American soldier.

Obama
had gone twice before to Afghanistan as president, most recently in
December 2010, and once to Iraq in 2009. All such trips, no matter how
carefully planned, carry the weight and the risks of considerable
security challenges. Just last month, the Taliban began
near-simultaneous assaults on embassies, government buildings and NATO
bases in Kabul.

Besides the U.S. troops in Afghanistan, there are 40,000 in coalition forces from other nations.

Obama
has already declared that NATO forces will hand over the lead combat
role to Afghanistan in 2013 as the U.S. and its allies work to get out
by the end of 2014.

One important unsettled issue, however, is how many U.S. troops may remain after that.

U.S.
officials are eying the 20,000 residual forces to work mostly in
support roles for the Afghan armed forces, and some U.S. special forces
for counterterror missions. The size and scope of that U.S. force if
one can be agreed upon on at all, given the public moods and political
factors in both nations will probably have to be worked out later in
a separate agreement.

Overall, polling shows, Obama gets
favorable marks compared to Romney in handling terrorism, and the
president's public approval for his handling of the Afghan war has
hovered around 50 percent of late.

The trip allows Obama to hold
forth as commander in chief in the same week he plans to launch his
official campaign travel with rallies in Virginia and Ohio.

"We've
spent the last three-and-a-half years cleaning up after other folks'
messes," Obama said at a fundraiser last weekend. "The war in Iraq is
over. We're transitioning in Afghanistan. Al-Qaida is on the ropes.
We've done what we said we'd do."